Page:Life of Sir William Petty 1623 – 1687.djvu/208

 convenience to the law-giver and the State, or are right from a purely ethical point of view. The 'Oceana' of Harrington, published in 1658, further proclaimed the opinion that the distribution of property determines the nature of government, and that the political philosopher is therefore concerned with the distribution of property.

Petty, as already seen, had been the pupil of Hobbes and the ally of Harrington in his club; and it was to Harrington that the popular belief attributed the original idea of the settlement of Ireland in which Petty had just played so conspicuous a part. Thus all the influences most likely to affect him, those of his own pursuits and of his social surroundings, combined to attract him to the examination of those questions which the final break-up of the old order of things founded on the ideas of the feudal system, and the rising influence of the trading and commercial classes, imperatively indicated as requiring an answer on something better than a merely empirical basis. As Petty possessed the mathematical faculty in a marked degree, his natural impulse was to attempt to apply mathematical methods and arguments drawn from figures to the elucidation of economic questions; though whether he was the inventor of the term 'political arithmetick' may be doubted: it was probably already a current term. Thus in his hands political economy was to be mainly an inductive science.

'By political arithmetick,' says Sir William Davenant, 'we mean the art of reasoning by figures upon things relating to government. The art itself is undoubtedly very ancient, but the application of it to the particular objects of trade and revenue is what Sir William Petty first began.... He first gave it that name, and brought it into rules and methods. At the time,' Davenant proceeds, 'the very foundation of the art, viz. reliable statistics, and more especially a competent knowledge of the numbers of the people, was wanting.' Sir William, therefore, in all his inquiries 'had to take the figures of the customs, excise, and hearth money as his guides, and to reason from them, trying to compute the number of the people from the consumption of the nation as evidenced by